1. Field of the Invention
The invention relates to the field of power semiconductor electronics. It is based on a power semiconductor module according to the preamble of the first claim.
2. Discussion of Background
Such a power semiconductor module is already described in European Patent Application EP 0 597 144 A1. Power semiconductor modules of the generic type comprise a housing in which at least one semiconductor chip is arranged on a baseplate, which may also simultaneously be used for cooling purposes. The semiconductor chips are electrically connected to outwardly routed terminals and, given a plurality of chips, are electrically interconnected by means of contact tracks. The cavity between housing cover and baseplate may be filled with a potting compound, for example an insulating gel. With a free gas volume in the housing, there is the risk in the longer term of the gel detaching under its own weight from the surface of the electronic components and, consequently, no longer being able to ensure high-voltage insulation.
These modules may be part of a power converter circuit arrangement. If a short circuit occurs in such a circuit arrangement, then it may destroy parts of the circuit arrangement. A short circuit in a module can easily lead to explosion of the module if suitable countermeasures are not taken.
The article "Reliable 1200 Amp 2500 V IGBT Modules for Traction Applications", IEE IGBT Propulsion Drives Colloquium, London, 25th April 1995 therefore proposes providing the housing with desired breaking points which limit the maximum pressure in the module. The housing ruptures at these desired breaking points in the event of an explosion, and gel or parts of the module can escape through the opening formed. However, housing parts flying around or gel hurled out constitute an undesirable source of danger. Material is sprayed around, contaminating the surroundings, and may lead to total failure of the device.